Lock ring for edgewise bracket

ABSTRACT

An orthodontic appliance for locking an archwire or archwires to an edgewise orthodontic bracket, and to provide movement control wherein the appliance is in the form of a ring that fits over the projections of the bracket and is locked in place on the projections to lock the archwire in the archwire slot. Lingual extensions may be provided on the ring for engagement with the archwire to provide mesio-distal inclination control when using round wire, and additionally labio-lingual control when using rectangular wire.

United States Patent [1 1 Kesling LOCK RING FOR EDGEWISE BRACKET [76]Inventor: Peter C. Kesling, Green Acres, La

Porte, Ind

[22] Filed: July 16, 197] [2]] Appl. No.: 163,313

[52] US. Cl. ..32[l4 A [51] Int. Cl ..A6lc 7/00 [58] Field of Search.32/14 A [56] References Cited UNITED STATES PATENTS Gladstone ..32/ l 4A Hoffman ..32/14 A [4 1 May 1, 1973 Primary ExaminerRobert PeshockAltorney-Lloyd L. Zickert 57] ABSTRACT An orthodontic appliance forlocking an archwire or archwires to an edgewise orthodontic bracket, andto provide movement control wherein the appliance is in the form of aring that fits over the projections of the bracket and is locked inplace on the projections to lock the archwire in the archwire slot.Lingual extensions may be provided on the ring for engagement with thearchwire to provide mesio-distal inclination control when using roundwire, andwadditionally labiolingual control when using rectangular wire.

20 Claims, 14 Drawing Figures Patented May 1, 1973 3,729,826

2 Sheets-Sheet 2 ullml I My} 75 Inventor Peter C. Ke sling Y LOCK RINGFOR EDGEWISE BRACKET This invention relates in general toorthodonticappliances, and more particularly to a lock ring for use withedgewise brackets to lock an archwire to the bracket, and still moreparticularly to a lock ring that may be constructed to additionallyprovide control movements effected by the archwire.

The present invention is intended for use with edgewise andedgewise-type brackets used in treating patients by the edgewiseorthodontic technique, and where both the usual rectangular incross-section edgewise archwire and round in cross-section archwire maybe used in treatment.

The term edgewise herein is intended to apply to any bracket having aslot opening buccally or labially where the archwire may be insertedfrom the buccal or labial side of the bracket, and where bothrectangular and round archwire may be used. Labial as used hereafter isintended to include buccal.

The usual edgewise bracket is defined by a pair of spacedoccluso-gingivally aligned and labially extending lugs or projectionsdefining therebetween a mesiodistally extending archwire slot. Notchesare normally provided on the projections for locking the archwire to thebracket, such as illustrated in U. S. Pat. No. 3,391,461. Theapplication of and removal of ligature wire is time consuming andtroublesome. Further, ligature wire cannot provide axial inclinationchanges by its engagement with the arch wire.

It has been proposed to use caps or clips to lock archwires in place onedgewise brackets, such as in U. S. Pat. Nos. 3,128,552 and 3,256,602,but such do not have the ability to increase the control or tooth movingforces delivered from the archwire to the tooth. Moreover, they protrudelabially from the bracket adding to the bulk of the appliance and thediscomfort to the patient.

Heretofore, when it was desired to facilitate the control of rootmovements of teeth, edgewise brackets were provided having an angularlyextending archwire slot, or were attached to the teeth with the slots atangles other than 90 to the long axis of the teeth, but suchwouldnecessitate the removal of the band and bracket and replacementwhen in a later treatment state it was necessary to have a differentslot-tooth relationship.

The lock ring of the invention in its most basic form includes aring-shaped body, the center opening of which is adapted to receive theprojections or lugs of an edgewise bracket. The lock ring may be made ofdead soft metals, such as stainless steel or brass, in which case thering is formed so that it may easily slip over the projections of thebracket and thereafter be deformed so the opposite ends are broughttoward each other into locking engagement with the notched portions ofthe projections. In this position, the mesial and distal sides of thering are arranged along the mesial and distal sides of the lugs and thelabial surface of the lock ring is substantially flush or lingual to theouter ends of the lugs whereby the lock ring does not protrude labiallybeyond the projections. The mesial and distal sides of the lock ringfunction to hold the archwire in the archwire slot of the bracket, andto provide rotational control between the bracket and the wire.

In another form, the ring body may have lingually facing projections ornotches to engage the wire thereby additionally providing mesial-distalinclination control between the wire and bracket. Where the wire isrectangular, these projections or notches may also provide labio-lingualtorque control between the bracket and archwire.

The lock ring of the invention may also be made of resilient material(metallic or non-metallic) in the shape it would take when in lockedposition on a bracket wherein the lock ring would be deformed so that itmay be applied to the bracket, and thereafter return to its originalshape in locking position on the bracket.

Accordingly, it is an object of the present invention to provide a newand improved orthodontic appliance for locking archwires to edgewisetype brackets.

Another object of this invention is in the provision of a lock ring foredgewise brackets that may be simply and easily installed and/or removedfrom a bracket for quickly and easily locking an archwire to or removingan archwire from a bracket.

Still another object of this invention is in the provision of a lockring for an edgewise bracket wherein the lock ring includes means forobtaining control movements between the bracket and the archwire.

A further object of this invention is to provide a lock ring for anedgewise type bracket that eliminates the need of ligature wire forlocking an archwire to the bracket.

A still further object of the invention is to provide a lock ring for anedgewise bracket capable of coacting with the bracket and archwire toprovide rotational and mesio-distal inclination control with any roundor rectangular wire and additionally labio-lingual torque control withrectangular wire.

Another object of the invention is to provide a lock ring for use withan edgewise bracket that coacts with the bracket to provide root controlor changes in direction of root control without necessitating change ofthe bracket or modification of the archwire.

Other objects, features and advantages of the invention will be apparentfrom the following detailed disclosure, taken in conjunction with theaccompanying sheets of drawings, wherein like reference numerals referto like parts, in which:

FIG. 1 is a front, elevational view ofa lock ring in accordance with theinvention arranged on an edgewise bracket, wherein the lock ring isshown in its form for initial placement on the bracket;

FIG. 2 is a vertical, sectional view taken through the embodiment ofFIG. 1;

FIG. 3 is a perspective view of the embodiment of FIG. 1 but showing thelock ring in locking position on the bracket;

FIG. 4 is a perspective view of a modified lock ring according to theinvention and which includes a lingual extension for obtainingmesio-distal control movement;

FIG. 5 is a perspective view of a still further modified lock ring inaccordance with the invention and shown in association with an edgewisebracket and where lingually extending ears define a notch to engage thearchwire to provide control of the mesio-distal inclination of thebracket or tooth, and where the wire is held perpendicularly to theoccluso-gingival axis of the bracket;

FIG. 6 is a front, elevational view of a further embodiment whichdiffers from the embodiment of FIG. in that the labially extendingprojections cause the archwire to be angularly disposed relative to theoccluso-gingival axis of the bracket,

FIG. 7 is a side elevational view of a further embodiment illustratingthe lock ring of the invention formed to provide a desiredlabial-lingual axial relationship between the arch wire and the bracket;

FIG. 8 is an exploded perspective view of a further modified lock ringand a bracket with an archwire in its slot, wherein the lock ring isillustrated in its form prior to being locked onto a bracket;

FIG. 9 is a perspective view of the embodiment of FIG. 8 wherein thelock ring is shown in looking engagement with the bracket;

FIG. 10 is a front, elevational view of the lock ring shown in FIGS. 8and 9, but illustrated in combination with an edgewise bracket arrangedto receive a rectangular in cross-section archwire.

FIG. 11 is a side, elevational view of the arrangement shown in FIG. 10;

FIG. 12 is a top plan view of the arrangement shown in FIGS. 10 and 11;

FIG. 13 is a perspective view of a further lock ring embodiment whichdiffers from the embodiment of FIGS. 8-12 only in that lingual facingnotches are provided to give mesio-distal inclination control; and

FIG. 14 is a perspective view of a lock ring and bracket arrangement,wherein the lock ring is of the same type as shown in FIGS. 8 to 12, butwherein the bracket is of a type that is capable of receiving anuprighting spring for applying an uprighting force to the bracket.

Referring now to the drawings, and particularly to FIGS. 1 to 3, thelock ring according to the invention, generally designated by thenumeral 15, is illustrated with an edgewise bracket 16, and a round incross-section archwire 17. FIGS. 5 to 7 illustrate a modification of thelock ring to coact with rectangular in cross-section archwire. It shouldbe appreciated that round or rectangular ar'chwire may be used dependingupon the choice of the operator and the desired stage of treatment.

The edgewise bracket 16 illustrated in FIGS. 1 to 3 includes a pad orbase 18 which would be suitably secured directly to a tooth by adhesive,or to a band by welding or soldering. The band, in turn, would besuitably cemented to a tooth in a patients mouth. The occluso-gingivalaxis of the bracket is illustrated as being along the vertical and apair of lugs, posts or projections 19 and 20 extend labially of the pad18 defining therebetween an ,archwire slot 21 which extendsmesio-distally. In the embodiment of FIGS. 1 to 3, the archwire slot isillustrated as being wider than the diameter of the archwire whichpermits mesio-distal tipping action between the archwire and thebracket.

' However, it should be appreciated that if no tipping action is desiredthe archwire slot may have a width the same as the width of thearchwire, that is, where essentially zero tolerance is provided betweenthe slot and the archwire, such as shown in FIGS. 10 and 11.

The upper and lower sides of the lugs 19 and 20 are notched at 22 and 23respectively to permit purchase of the lock ring to the bracket.Heretofore, the notches have served as hooks or the like for receiving aligature wire when locking the archwire in place on an edgewise bracket.The labio-lingual depth of the lugs 19 and 20 may vary depending uponthe desired usage of the bracket. For example, extensions areillustrated in phantom in FIG. 2 which would allow a further wire 17a tobe secured to the bracket in the archwire slot labial of the lock ringby using a ligature wire retained by the openings 22a and 23a. The termedgewise used herein to define the bracket is intended to apply to anybracket having a mesio-distal archwire slot. It should be recognized thenotches may be formed along the mesial and distal sides of the posts oralong the occlusal and gingival sides of the posts as shown.

The bracket could be made of any suitable dead soft or resilientmaterial, such as stainless steel or plastic. When made of stainlesssteel, it could be milled while when made of plastic it could be molded.It should also be appreciated that the bracket may be formed from astamping. It should be further understood that the bracket forms no partof the present invention and that it is well known.

The lock ring 15 includes opposed sides 24 and 2S and opposed ends 26and 27, all interconnected and formed as a body in the shape of a ringto define a central opening 28. The various sides are generallyrectangular in cross-section, although they may take any othergeometrical shape. The opposed sides 24 and 25 are oppositely, arcuatelyformed to insure proper deformation when the lock ring is compressed orsqueezed along the occluso-gingival axis and locked to the bracket, andsubsequently compressed or squeezed along the mesio-distal axis to beremoved from the bracket. The upper and lower ends 26 and 27 are offsetlingually from the opposed sides a sufficient distance so that they willenter the notches 22 and 23 when the lock ring is squeezed into lockingposition. As shown in FIG. 3, the direction of squeeze is along theocclusogingival axis, as indicated by the arrows 29 and 30, which bringsthe upper and lower ends 26 and 27 into locking engagement with thelugs, as seen in FIG. 3 and spreads the sides apart.

When the lock ring is made of a dead soft metal, the deformation of thering will remain as shown in FIG. 3, where the upper and lower ends ofthe ringare hooked over the lugs 19 and 20 so that the lock ring islocked into position. As noted in FIG. 2, the outer surface of the lockring is substantially flush with the labial surface of the lugs so thatthe lock ring does not protrude labially from the bracket and into themouth. This minimizes, if not eliminates, any possible irritation to thepatients mouth, and the possible displacement of the ring when thepatient is chewing on food. The lock ring, after positioning over thelugs, is locked in position by applying the jaws of a pliers to theupper and lower ends 26 and 27 and squeezing until the ends 26 and 27are seated in the notches. It is a simple matter to remove the ring fromthe bracket by applying a pliers to the opposed sides 24 and 25 to forceapart the ends 26 and 27 thereby elongating the opening 28 and spreadingapart the ends and allowing the lock ring to be withdrawn labially fromthe bracket lugs. When in locked position, it can be seen the sides 26and 25 coact with the base or pad 18 to, at the mesial and distal sidesof the lugs 19 and 20, contain the archwire to achieve rotationalcontrol between the bracket and archwire.

Where the lock ring may be molded of a resilient material, such as oneof the many plastics available, like nylon, it would in its passivestate take the form shown in FIG. 3 and be deformed during theapplication of the ring to the bracket. Deformation would involve thesqueezing toward one another of the opposite sides 24 and 25 until theopposite ends 26 and 27 are far enough apart so that they may slide overthe lugs 19 and 20.

In order to eliminate relative rotation between the lock ring andbracket, the opening at the top and bottom is narrowed to just clear theopposite sides of the lugs, and to this end guide faces 26a and 27a areprovided.

The embodiment of FIG. 4, generally designated by the numeral 35,differs from the embodiment of FIGS. 1 to 3 only in that a linguallyextending ear is provided on one of the sides for the purpose ofproducing a control movement between the archwire and the bracket. Thislock ring includes opposed sides 36 and 37 and opposed ends 38 and 39.At the side 36 an ear or projection 40 extends lingually for the purposeof defining an archwire stop. For example, should the tooth on which theappliance is mounted require tipping movement and it be further desiredthat the tipping movement cease when the tooth is in an uprightposition, the lock ring could then be used and which would effectivelyprovide a mesio-distal inclination control. If the ear were on thedistal side of the bracket and occlusal to the archwire and the toothwere initially tipped with its occlusal end being mesial to the desiredinclination, distal tipping would cease when the tooth reached theupright position where the archwire would engage the ear 40. It must beassumed here that the archwire will always tend to assume aperpendicular position with respect to the desired occluso-gingivalposition of the tooth. It should be appreciated here that the ear 40extends from the lower end of the side 36, although for opposite controlit could extend from the lower end of the side 37. Application andremoval of the lock ring 35 would be accomplished in the same manner asabove described with lock ring 15.

Another form of lock ring, according to the invention, is shown in FIG.5 and generally designated by the numeral 42. This lock ring isespecially useful for application to the bracket of FIG. 1 and toprovide in addition to mesio-distal inclination control labio-lingualcontrol by using rectangular in cross-section archwire 43. In thisembodiment, the lock ring provides opposed sides 44 and 45interconnected by opposed ends 46 and 47. The sides are like theembodiments of FIGS. 1 and 4 in that they are bowed outwardly to controldeformation in the application to and removal of the lock ring from abracket. At each of the opposed sides 44 and 45, a pair of linguallyextending ears 48 coact to define an archwire slot 49 sized to receivethe rectangular archwire 43 and to prevent rotation and tipping betweenthe archwire and lock ring. The archwire is captured by the ears 48which extend sufficiently toward the base 18 of the bracket so that itcannot slip around the ends of the ears. Application and removal of thislock ring may be accomplished in the same fashion as described inconnection with the embodiment of FIG. 1. Further the ears 48 extendingfrom the opposite sides 44 and 45 are positioned to place the archwire43 perpendicularly with respect to the occluso-gingival axis of thebracket 16. It should be further appreciated that this lock ring couldbe used with round wire and the bracket 16 where no mesiodistal tippingwould be desired.

The embodiment of FIG. 6 differs from the embodiment of FIG. 5 only inthat the ears represented by Xs 50 are arranged to hold the archwire 43in an angular relation to the bracket other than the perpendicularrelation shown in FIG. 5. This bracket is generally designated by thenumeral 420. While shown as used with rectangular wire, it couldlikewise be used with round wire.

The lock ring embodiment in FIG. 7, where the lock ring is generallydesignated 42B, differs from the lock ring 42 in the angulation of theslot 49b which is arranged to change the labial-lingual inclination ofthe tooth.

Another lock ring embodiment of the invention is illustrated in FIGS. 8and 9 which differs from the embodiment of FIG. I only in the shape ofthe sides and initial positioning of the ends for illustrating anothermode of application to a bracket. The bracket is the same as shown inFIGS. 1 to 5 and is therefore identified by the same numerals. Thisembodiment is also illustrated in use with a round archwire. The lockring here is generally designated by the numeral 55 and includesparallel opposed and spaced sides 56 and 57 and opposed ends 58 and 59interconnected with the sides and defining a central opening 60. Theopening 60 is initially sized when the lock ring is made of dead softmetal 50 that the lock ring may easily slip over the lugs of thebracket. Once the lock ring is in position, by using a pliers, theopposite ends 58 may be bent toward each other to engage in the notches22 and 23 of the lugs and lock the ring onto the bracket with thearchwire in place, as shown in FIG. 9. In order to facilitate thebending of the ends 58 and 59 toward each other and with respect to theopposed sides 56 and 57, the ends include cross bar portions 58a and 59ahaving short end portions 58b and 59b forming continuations of the sides56 and 57. Further notches or scores 58c and 590 are provided at thejunction of the sides with the end portions to facilitate bending andprevent fracturing when the lock ring is applied to a bracket. Again thesides 56 and 57 of the lock ring capture the archwire at mesial anddistal sides of the lugs against the base 18 to prevent rotation of thebracket relative the archwire while permitting tipping action. Thelabial faces of the lock ring are substantially flush with the labialfaces of the lugs, although it should be appreciated that these lockring faces could be recessed lingually with respect to the labial facesof the lugs. Removal of the lock ring 55 is accomplished by spreadingthe ends 58 until they clear the lugs. As with the embodiment of FIG. 1,if lock ring 55 were made of plastic, it would take the form shown inFIG. 9 and be deformed to spread the ends when applying and removingsame from a bracket.

The use of rectangular archwire with an edgewise bracket defining anarchwire slot that will prevent mesio-distal and labio-lingual tippingmovements between the archwire and bracket is illustrated in FIGS. 10 to12 where the bracket is generally designated by the numeral 65. The lockring 55 of the embodiment shown in FIGS. 8 and 9 is illustrated herealthough it should be appreciated that the lock ring of FIG. 1 couldlikewise be employed. The bracket 65 includes a base or pad 66 having apair of lugs 67 and 68 extending therefrom and which definestherebetween an archwire slot 69 of rectangular cross-section which issized about the same as the archwire 43, allowing for tolerances, butwhich will not permit relative rotation between the archwire and lugs orrelative tipping action between the archwire and lugs. Otherwise, thelock ring performs as with the other edgewise bracket.

The lock ring embodiment of FIG. 13, generally designated as 55A,differs from the lock ring of FIGS. 8 to 12 only in that linguallyextending lugs 70 define a lingually facing archwire slot 71 to providemesio-distal inclination control. Where rectangular archwire as shown isused which is sized to snugly fit in the slot, labio-lingual rootcontrol is also achieved.

FIG. 14 merely illustrates another form of edgewise bracket on which thelock ring of the present invention may be employed to emphasize that thelock ring is intended to be used on any type of edgewise bracket wherethe wire may be inserted from the labial side of the bracket into anarchwire slot opening labially. This bracket is generally identified bythe numeral 73 and is made from a stamping that is thereafter formed tothe shape illustrated wherein a pair of lugs 74 and 75 extend labiallyfrom a pair of welding or attaching flanges 76 and 77. An archwire slot78 is defined between the lugs and which may be sized to receive roundor rectangular wire that would permit relative tipping between the wireand the bracket. Further the lugs 74 and 75 are provided withoccluso-gingival extending and aligned openings 74a and 750 which wouldpermit the reception of one end of an uprighting spring, the other endof which would engage the archwire and where the uprighting spring wouldfunction to apply an uprighting force to the tooth on which theappliance is mounted. While the lock ring 55 is illustrated inconnection with bracket 73, it should be appreciated that any of thelock rings illustrated may be used.

It will be understood that modifications and variations may be effectedwithout departing from the scope of the novel concepts of the presentinvention, but it is understood that this application is to be limitedonly by the scope of the appended claims.

The invention is hereby claimed as follows:

1. The combination of an edgewise bracket and an appliance for lockingan archwire to the bracket, wherein the bracket includes a pair ofspaced occlusogingivally aligned projections defining therebetween amesio-distally extending archwire slot and the projections are notchedat the outer edges thereof, said appliance comprising a ring-shapedframe formed to slip over the projections when being first positioned onthe bracket and thereafter be formed into locking position with thenotches to lock an archwire in said slot and to be substantially flushwith the labia] surface of the projections, and means at the occlusaland gingival ends of the frame closely fitting with the mesial anddistal sides of the projections to prevent relative rotation between theframe and bracket.

2. The appliance of claim 1, wherein the projections are spaced apart adistance greater than the thickness of the archwire to enable tippingbetween the wire and bracket, and control means extending lingually ofthe frame to coact with the wire and control relative movement betweenthe wire and bracket.

3. The appliance of claim 2, wherein said control means includes an earat one side of the appliance extending lingually into the path of thearchwire to limit mesio-distal tooth tipping thereby.

4. The appliance of claim 2, wherein said control means includes aplurality of ears at one side of the appliance capturing the archwire toprovide relative mesio-distal tipping movement control between the wireand bracket.

5. The combination of a bracket and a lock ring for securing an archwireto said bracket, wherein said bracket includes a base and a pair ofspaced and 0ccluso-gingivally aligned lugs labially projecting therefromdefining therebetween a mesio-distally extending archwire slot, eachsaid lug having a notch at the side thereof opposite the archwire slot,said lock ring comprising opposed sides to be positioned on the mesialand distal sides of the lugs, means on the opposed sides coacting withthe lugs to prevent relative rotation between the lock ring and bracket,opposed ends interconnected between the sides to be positioned at theocclusal and gingival sides of the lugs and formed to engage in the lugnotches, said sides and ends defining therebetween an opening, said endsbeing initially spaced apart so the opening is sized to permit the lockring to slip over the lugs to thereafter permit the ends of the lockring to move toward one another into said notches and into lockingengagement with said lugs.

6. A lock ring as defined in claim 5, wherein said sides are bowedoutwardly to facilitate deformation of the lock ring when locking andunlocking same to a bracket.

7. A lock ring as defined in claim 5, wherein said sides include meanscoacting with the lugs to provide relative mesio-distal rotation controlbetween the bracket and lock ring.

8. The combination of claim 5, where the ring is of dead soft metal, anddeformable into locking position on the bracket.

9. A lock ring as defined in claim 8, and scores between the sides andends to facilitate bending of the ends toward each other.

10. The combination of claim 5, where the ring is of plastic, andsnapable into locking position on the bracket.

11. A lock ring as defined in claim 6, and means extending linguallyfrom one of said sides to effect labiolingual control between thebracket and archwire.

12. A lock ring as defined in claim 5, wherein the labial surfaces ofsaid lock ring are substantially flush with the labial surfaces of saidlugs, and the lingual surfaces of the lock ring coact with the base tocapture the archwire and provide rotational control between the bracketand archwire while permitting relative tipping therebetween where thearchwire slot is larger than the wire thickness.

13. A lock ring as defined in claim 5, and means extending linguallyfrom at least one of said sides of the lock ring to provide mesio-distalinclination control between the bracket and archwire.

14. A lock ring as defined in claim 13, wherein said means includes anear defining an archwire stop.

15. A lock ring as defined in claim' 13, wherein said means includes apair of ears defining an archwire slot.

16. A lock ring as defined in claim 15, wherein said ears are positionedto hold the archwire normal to the occluso-gingival axis of the bracket.

17. A lock ring as defined in claim 15, wherein said ears are positionedto hold the archwire non-normal to the occluso-gingival axis of thebracket.

18. A lock ring as defined in claim 13, wherein said means includes apair of ears on each of said sides defining an archwire slot.

19. A lock ring as defined in claim 18, wherein the slot defined by theears is sized for rectangular wire and functions to provide relativemesio-distal and labio-lingual axial control between the wire and thebracket.

20. The combination of an edgewise bracket and an appliance for lockingan archwire to the bracket, wherein the bracket includes a base forattachment to a band or tooth, a pair of occluso-gingivally aligned andspaced posts projecting labially and defining therebetween amesio-distally extending archwire slot, and the posts formed to coactwith the base and define notches, said appliance comprising aring-shaped body sized to slip over the posts when being firstpositioned on the bracket and thereafter be formed into locking positionwith the posts by having means engaging into the notches to thereby lockan archwire in said slot, and means on the body coacting with the lugsto prevent relative rotation between the lock ring and bracket.

1. The combination of an edgewise bracket and an appliance for lockingan archwire to the bracket, wherein the bracket includes a pair ofspaced occluso-gingivally aligned projections defining therebetween amesio-distally extending archwire slot and the projections are notchedat the outer edges thereof, said appliance comprising a ring-shapedframe formed to slip over the projections when being first positioned onthe bracket and thereafter be formed into locking position with thenotches to lock an archwire in said slot and to be substantially flushwith the labial surface of the projections, and means at the occlusaland gingival ends of the frame closely fitting with the mesial anddistal sides of the projections to prevent relative rotation between theframe and bracket.
 2. The appliance of claim 1, wherein the projectionsare spaced apart a distance greater than the thickness of the archwireto enable tipping between the wire and bracket, and control meansextending lingually of the frame to coact with the wire and controlrelative movement between the wire and bracket.
 3. The appliance ofclaim 2, wherein said control means includes an ear at one side of theappliance extending lingually into the path of the archwire to limitmesio-distal tooth tipping thereby.
 4. The appliance of claim 2, whereinsaid control means includes a plurality of ears at one side of theappliance capturing the archwire to provide relative mesio-distaltipping movement control between the wire and bracket.
 5. Thecombination of a bracket and a lock ring for securing an archwire tosaid bracket, wherein said bracket includes a base and a pair of spacedand occluso-gingivally aligned lugs labially projecting therefromdefining therebetween a mesio-distally extending archwire slot, eachsaid lug having a notch at the side thereof opposite the archwire slot,said lock ring comprising opposed sides to be positioned on the mesialand distal sides of the lugs, means on the opposed sides coacting withthe lugs to prevent relative rotation between the lock ring and bracket,opposed ends interconnected between the sides to be positioned at theocclusal and gingival sides of the lugs and formed to engage in the lugnotches, said sides and ends defining therebetween an opening, said endsbeing initially spaced apart so the opening is sized to permit the lockring to slip over the lugs to thereafter permit the ends of the lockring to move toward one another into said notches and into lockingengagement with said lugs.
 6. A lock ring as defined in claim 5, whereinsaid sides are bowed outwardly to facilitate deformation of the lockring when locking and unlocking same to a bracket.
 7. A lock ring asdefined in claim 5, wherein said sides include means coacting with thelugs to provide relative mesio-distal rotation control between thebracket and lock ring.
 8. The combination of claim 5, where the ring isof dead soft metal, and deformable into locking position on the bracket.9. A lock ring as defined in claim 8, and scores between the sides andends to facilitate bending of the ends toward each other.
 10. Thecombination of claim 5, where the ring is of plastic, and snapable intolocking position on the bracket.
 11. A lock ring as defined in claim 6,and means extending lingually from one of said sides to effectlabio-lingual control between the bracket and archwire.
 12. A lock ringas defined in claim 5, wherein the labial surfaces of said lock ring aresubstantially flush with the labial surfaces of said lugs, and thelingual surfaces of the lock ring coact with the base to capture thearchwire and provide rotational control between the bracket and archwirewhile permitting relative tipping therebetween where the archwire slotis larger than the wire thickness.
 13. A lock ring as defined in claim5, and means extending lingually from at least one of said sides of thelock ring to provide mesio-distal inclination control between thebracket and archwire.
 14. A lock ring as defined in claim 13, whereinsaid means includes an ear defining an archwire stop.
 15. A lock ring asdefined in claim 13, wherein said means includes a pair of ears definingan archwire slot.
 16. A lock ring as defined in claim 15, wherein saidears are positioned to hold the archwire normal to the occluso-gingivalaxis of the bracket.
 17. A lock ring as defined in claim 15, whereinsaid ears are poSitioned to hold the archwire non-normal to theoccluso-gingival axis of the bracket.
 18. A lock ring as defined inclaim 13, wherein said means includes a pair of ears on each of saidsides defining an archwire slot.
 19. A lock ring as defined in claim 18,wherein the slot defined by the ears is sized for rectangular wire andfunctions to provide relative mesio-distal and labio-lingual axialcontrol between the wire and the bracket.
 20. The combination of anedgewise bracket and an appliance for locking an archwire to thebracket, wherein the bracket includes a base for attachment to a band ortooth, a pair of occluso-gingivally aligned and spaced posts projectinglabially and defining therebetween a mesio-distally extending archwireslot, and the posts formed to coact with the base and define notches,said appliance comprising a ring-shaped body sized to slip over theposts when being first positioned on the bracket and thereafter beformed into locking position with the posts by having means engaginginto the notches to thereby lock an archwire in said slot, and means onthe body coacting with the lugs to prevent relative rotation between thelock ring and bracket.